Biprojectivty of Banach algebras modulo an ideal
Subject Areas : Statistics
M.
ghorbani
1
(Department of Mathematics, Faculty of Science, Central Tehran branch, Islamic Azad university)
H.R.
rahimi
2
(Department of Mathematics, Faculty of Science, Central Tehran
Branch, Islamic Azad University, Tehran, Iran)
Keywords: دوتصویری بودن نسبت به ایدهآل, انقباضپذیری نسبت به ایدهآل, جبر نیمگروهی, همنهشتی گروهی, مدول باناخ,
Abstract :
In this paper, we introduce the new concept of biprojectivity of a Banach algebra modulo an ideal, as a generalization of this notion in the classical case. By using it , we obtain some necessary and sufficient conditions for contractibility of Banach algebras modulo an ideal. In particular we characterize the contractibility of quotient Banach algebras. Also we study the relationship between the biprojectivity modulo an ideal of a Banach algebra and the biprojectivity of the corresponding quotient Banach algebra. ....
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